The disclosed subject matter relates to a thermal control system for fault detection and mitigation within a power generation system.
Certain power generation systems include a gas turbine engine configured to combust a mixture of fuel and compressed air to produce hot combustion gases. The combustion gases may flow through a turbine to generate power for a load, such as an electric generator. To enhance efficiency, certain power generation systems employ a heat recovery steam generator (HRSG) to capture energy from the hot combustion gases exhausted from the turbine. In general, HRSGs convey a fluid, such as water, through multiple conduits in a direction crosswise (e.g., substantially perpendicular) to the flow of exhaust gas. As the exhaust gas flows across the conduits, heat is transferred from the exhaust gas to the water, thereby producing steam. The steam is then directed through a steam turbine to generate rotational motion, thereby driving a load, such as an electric generator. Certain HRSGs include conduits having fins configured to increase heat transfer between the exhaust gas and the water flow through the conduits. Unfortunately, separation of the fins from the conduits may decrease HRSG efficiency. In addition, if a portion of the exhaust flow is warmer than desired, certain conduits may experience excessive steam pressure, thereby resulting in premature wear of certain HRSG components.
Furthermore, certain power generation systems include a switchgear configured to regulate operation of various electrical systems, such as electrical output from the generators and/or an electrical starter motor for the gas turbine engine. Due to the high voltage and amperage passing through the switchgear, the switchgear is typically scanned with an infrared camera prior to activation of the power generation system. For example, a technician may open each electrical enclosure of the switchgear, and then direct the infrared camera toward an interior of each enclosure to ensure that the temperature is within a desired limit. Because an excessive temperature may be indicative of an electrical short or a loose connection within the switchgear, corrective action may be taken if an excessive temperature is detected. Unfortunately, the process of manually scanning the switchgear is expensive and time-consuming, thereby increasing the operational costs of the power generation system.
In addition, certain power generation systems include a generator step-up transformer (GSU) to increase the generator voltage to a desired level for power transmission. The GSU is electrically coupled to the generator via an electrical connection, such as an isolated phase bus. In general, the isolated phase bus includes three electrical conduits configured to individually transfer each phase of the three-phase power output by the generator to the GSU. Each electrical conduit of the isolated phase bus typically includes an electrical conductor assembly disposed within an enclosure. The electrical conductor assembly is electrically isolated from the enclosure by a series of insulators which also serve to support the electrical conductor assembly within the enclosure. The electrical conductor assembly includes a series of conductors coupled to one another by fasteners, for example. As will be appreciated, the electrical conductors may separate from one another over time, thereby generating heat at the junction between conductors. Consequently, the power transfer efficiency of the isolated phase bus may be substantially reduced, thereby decreasing the efficiency of the power generation system.